Electronic communication devices are widely used for business and personal activities and are continually increasing in popularity. Advances in electronics and wireless communication technology, as well as the development of communication infrastructure, have fueled this increase in popularity and have greatly expanded the capabilities of wireless communication. A wide variety of newer and ever more sophisticated electronic communication devices are continually being introduced by manufacturers, including such devices as wireless phones (e.g., cellular phones), two-way radios (e.g., “walkie-talkies”), pagers and text messaging devices, portable and handheld computers, personal digital assistants (PDAs), satellite communication devices such as global positioning systems (GPSs), and satellite radios, as well as portable televisions, radios, and other entertainment devices.
Electronic communication devices typically have one or more antennas for signal reception and transmission. Several different types of antennas exist, including retractable antennas and fixed antennas. The use of a retractable antenna provides the user with a selectively longer or shorter antenna. A conventional retractable antenna for a wireless communication device is typically formed of a narrower extendable portion that includes a whip and cap, and a wider fixed portion (known as a body or stubby). In contrast, a fixed antenna has only a fixed part.
Consumers often prefer retractable antennas that can be extended when in use to increase reception and transmission efficiency, and retracted when not in use to protect the antenna from damage and reduce the overall size of the communication device so that the device can be easily stored.
The increase in the number of products on the market has lead to increasing competition between manufacturers, and emphasized the need for manufacturers to develop and implement product designs which differentiate their products from competing products in order to gain a competitive edge, attract new consumers, and to persuade existing consumers to upgrade to newer models. The design of the antenna of a wireless communication device is based on functional considerations, but also aesthetic considerations because the antenna typically makes a prominent contribution to the external appearance of the device.
Most retractable antennas are circular antennas that have a cylindrical whip topped by a cylindrical or circular cap so that the extendable portion appears circular in shape when viewed along its longitudinal axis. However, to differentiate its products functionally or aesthetically, a manufacturer can use a non-circular antenna that has a non-cylindrical whip and/or a cap with a radially non-symmetrical shape. Such non-circular retractable antennas may be desirable to consumers for a variety of reasons. For example, compared with circular antennas, a non-circular antenna may be more aesthetically interesting or pleasing, may be more easily handled during extension and retraction, may be less cumbersome when extended, and may be better integrated with the body of the device when retracted. Furthermore, from the manufacturer's perspective, a non-circular retractable antenna provides additional style options in the design of a new electronic communication device.
However, implementing a non-circular retractable antenna that is capable of extending and retracting in a smooth, quick, and efficient manner presents design challenges. For example, while a circular retractable antenna can be retracted at any angle of rotation, a non-circular retractable antenna typically must be aligned at some specific angle of rotation in order to fully retract. The extendable portion of a non-circular retractable antenna will not readily self-align to the proper angle of rotation, and any misalignment blocks the extendable portion from quickly and easily being fully retracted. If the antenna is not fully retracted due to misalignment, there is an increase in the likelihood of the antenna being becoming snagged on an external object, which can cause damage to the antenna or even loss of the device. Further, any difficulty in quickly and easily fully retracting the antenna can cause user frustration by making the communication device difficult to stow away.
Therefore a need exists to overcome the problems with the prior art as discussed above.